diff --git a/src/ace/Document.js b/src/ace/Document.js
index 442ebd27..3facbc99 100644
--- a/src/ace/Document.js
+++ b/src/ace/Document.js
@@ -562,4 +562,51 @@ ace.Document = function(text, mode) {
         return Math.max(0, Math.min(row, this.lines.length-1));
     };
 
+    this.documentToScreenColumn = function(row, docColumn) {
+        var tabSize = this.getTabSize();
+
+        var screenColumn = 0;
+        var remaining = docColumn;
+
+        var line = this.getLine(row).split("\t");
+        for (var i=0; i<line.length; i++) {
+            var len = line[i].length;
+            if (remaining > len) {
+                remaining -= (len + 1);
+                screenColumn += len + tabSize;
+            }
+            else {
+                screenColumn += remaining;
+                break;
+            }
+        }
+
+        return screenColumn;
+    };
+
+    this.screenToDocumentColumn = function(row, screenColumn) {
+        var tabSize = this.getTabSize();
+
+        var docColumn = 0;
+        var remaining = screenColumn;
+
+        var line = this.getLine(row).split("\t");
+        for (var i=0; i<line.length; i++) {
+            var len = line[i].length;
+            if (remaining >= len + tabSize) {
+                remaining -= (len + tabSize);
+                docColumn += (len + 1);
+            }
+            else if (remaining > len){
+                docColumn += len;
+                break;
+            }
+            else {
+                docColumn += remaining;
+                break;
+            }
+        }
+        return docColumn;
+    };
+
 }).call(ace.Document.prototype);
diff --git a/src/ace/Editor.js b/src/ace/Editor.js
index b1e53be1..97a959db 100644
--- a/src/ace/Editor.js
+++ b/src/ace/Editor.js
@@ -93,6 +93,7 @@ ace.Editor = function(renderer, doc) {
         this.doc.addEventListener("changeBreakpoint", this.$onDocumentChangeBreakpoint);
 
         this.selection = doc.getSelection();
+        this.$desiredColumn = 0;
 
         this.$onCursorChange = ace.bind(this.onCursorChange, this);
         this.selection.addEventListener("changeCursor", this.$onCursorChange);
@@ -279,10 +280,12 @@ ace.Editor = function(renderer, doc) {
 
     this.onMouseDoubleClick = function(e) {
         this.selection.selectWord();
+        this.$updateDesiredColumn();
     };
 
     this.onMouseTripleClick = function(e) {
         this.selection.selectLine();
+        this.$updateDesiredColumn();
     };
 
     this.onMouseWheel = function(e) {
@@ -467,6 +470,7 @@ ace.Editor = function(renderer, doc) {
         var addedColumns = this.doc.indentRows(this.getSelectionRange(), indentString);
 
         this.selection.shiftSelection(addedColumns);
+        this.$updateDesiredColumn();
     };
 
     this.blockOutdent = function(indentString) {
@@ -477,6 +481,7 @@ ace.Editor = function(renderer, doc) {
         var addedColumns = this.doc.outdentRows(this.getSelectionRange(), indentString);
 
         this.selection.shiftSelection(addedColumns);
+        this.$updateDesiredColumn();
     };
 
     this.toggleCommentLines = function() {
@@ -656,14 +661,17 @@ ace.Editor = function(renderer, doc) {
 
     this.clearSelection = function() {
         this.selection.clearSelection();
+        this.$updateDesiredColumn();
     };
 
     this.moveCursorTo = function(row, column) {
         this.selection.moveCursorTo(row, column);
+        this.$updateDesiredColumn();
     };
 
     this.moveCursorToPosition = function(pos) {
         this.selection.moveCursorToPosition(pos);
+        this.$updateDesiredColumn();
     };
 
 
@@ -680,16 +688,34 @@ ace.Editor = function(renderer, doc) {
     this.navigateTo = function(row, column) {
         this.clearSelection();
         this.moveCursorTo(row, column);
+        this.$updateDesiredColumn(column);
     };
 
     this.navigateUp = function() {
-        this.clearSelection();
-        this.selection.moveCursorUp();
+        this.selection.clearSelection();
+        this.selection.moveCursorBy(-1, 0);
+
+        if (this.$desiredColumn) {
+            var cursor = this.getCursorPosition();
+            var column = this.doc.screenToDocumentColumn(cursor.row, this.$desiredColumn);
+            this.selection.moveCursorTo(cursor.row, column);
+        }
     };
 
     this.navigateDown = function() {
-        this.clearSelection();
-        this.selection.moveCursorDown();
+        this.selection.clearSelection();
+        this.selection.moveCursorBy(1, 0);
+
+        if (this.$desiredColumn) {
+            var cursor = this.getCursorPosition();
+            var column = this.doc.screenToDocumentColumn(cursor.row, this.$desiredColumn);
+            this.selection.moveCursorTo(cursor.row, column);
+        }
+    };
+
+    this.$updateDesiredColumn = function() {
+        var cursor = this.getCursorPosition();
+        this.$desiredColumn = this.doc.documentToScreenColumn(cursor.row, cursor.column);
     };
 
     this.navigateLeft = function() {
@@ -715,39 +741,40 @@ ace.Editor = function(renderer, doc) {
     };
 
     this.navigateLineStart = function() {
-        this.clearSelection();
         this.selection.moveCursorLineStart();
+        this.clearSelection();
     };
 
     this.navigateLineEnd = function() {
-        this.clearSelection();
         this.selection.moveCursorLineEnd();
+        this.clearSelection();
     };
 
     this.navigateFileEnd = function() {
-        this.clearSelection();
         this.selection.moveCursorFileEnd();
+        this.clearSelection();
     };
 
     this.navigateFileStart = function() {
-        this.clearSelection();
         this.selection.moveCursorFileStart();
+        this.clearSelection();
     };
 
     this.navigateWordRight = function() {
-        this.clearSelection();
         this.selection.moveCursorWordRight();
+        this.clearSelection();
     };
 
     this.navigateWordLeft = function() {
-        this.clearSelection();
         this.selection.moveCursorWordLeft();
+        this.clearSelection();
     };
 
     this.replace = function(replacement) {
       var range = this.$tryReplace(this.getSelectionRange(), replacement);
       if (range !== null)
           this.selection.setSelectionRange(range);
+      this.$updateDesiredColumn();
     },
 
     this.replaceAll = function(replacement) {
@@ -763,6 +790,7 @@ ace.Editor = function(renderer, doc) {
             this.$tryReplace(range, replacement);
         }
         this.selection.setSelectionRange(range);
+        this.$updateDesiredColumn();
     },
 
     this.$tryReplace = function(range, replacement) {
@@ -800,8 +828,10 @@ ace.Editor = function(renderer, doc) {
         });
 
         var range = this.$search.find(this.doc);
-        if (range)
+        if (range) {
             this.selection.setSelectionRange(range);
+            this.$updateDesiredColumn();
+        }
     };
 
     this.undo = function() {
diff --git a/src/ace/VirtualRenderer.js b/src/ace/VirtualRenderer.js
index e7732de8..35f017c5 100644
--- a/src/ace/VirtualRenderer.js
+++ b/src/ace/VirtualRenderer.js
@@ -250,57 +250,10 @@ ace.VirtualRenderer = function(container) {
     this.$documentToScreenPosition = function(pos) {
         return {
             row: pos.row,
-            column: this.$documentToScreenColumn(pos.row, pos.column)
+            column: this.doc.documentToScreenColumn(pos.row, pos.column)
         };
     };
 
-    this.$documentToScreenColumn = function(row, docColumn) {
-        var tabSize = this.doc.getTabSize();
-
-        var screenColumn = 0;
-        var remaining = docColumn;
-
-        var line = this.doc.getLine(row).split("\t");
-        for (var i=0; i<line.length; i++) {
-            var len = line[i].length;
-            if (remaining > len) {
-                remaining -= (len + 1);
-                screenColumn += len + tabSize;
-            }
-            else {
-                screenColumn += remaining;
-                break;
-            }
-        }
-
-        return screenColumn;
-    };
-
-    this.$screenToDocumentColumn = function(row, screenColumn) {
-        var tabSize = this.doc.getTabSize();
-
-        var docColumn = 0;
-        var remaining = screenColumn;
-
-        var line = this.doc.getLine(row).split("\t");
-        for (var i=0; i<line.length; i++) {
-            var len = line[i].length;
-            if (remaining >= len + tabSize) {
-                remaining -= (len + tabSize);
-                docColumn += (len + 1);
-            }
-            else if (remaining > len){
-                docColumn += len;
-                break;
-            }
-            else {
-                docColumn += remaining;
-                break;
-            }
-        }
-        return docColumn;
-    };
-
     this.hideCursor = function() {
         this.$cursorLayer.hideCursor();
     };
@@ -369,7 +322,7 @@ ace.VirtualRenderer = function(container) {
 
         return {
             row : row,
-            column : this.$screenToDocumentColumn(Math.max(0, Math.min(row, this.doc.getLength()-1)), col)
+            column : this.doc.screenToDocumentColumn(Math.max(0, Math.min(row, this.doc.getLength()-1)), col)
         };
     };
 
diff --git a/src/test/ace/DocumentTest.js b/src/test/ace/DocumentTest.js
index 67814be0..25817208 100644
--- a/src/test/ace/DocumentTest.js
+++ b/src/test/ace/DocumentTest.js
@@ -162,5 +162,51 @@ var TextDocumentTest = new TestCase("TextDocumentTest", {
         undoManager.undo();
         doc.$informUndoManager.call();
         assertEquals(initialText, doc.toString());
+    },
+
+    "test: convert document to screen coordinates" : function() {
+        var doc = new ace.Document("01234\t567890\t1234");
+        doc.setTabSize(4);
+
+        assertEquals(0, doc.documentToScreenColumn(0, 0));
+        assertEquals(4, doc.documentToScreenColumn(0, 4));
+        assertEquals(5, doc.documentToScreenColumn(0, 5));
+        assertEquals(9, doc.documentToScreenColumn(0, 6));
+        assertEquals(15, doc.documentToScreenColumn(0, 12));
+        assertEquals(19, doc.documentToScreenColumn(0, 13));
+
+        doc.setTabSize(2);
+
+        assertEquals(0, doc.documentToScreenColumn(0, 0));
+        assertEquals(4, doc.documentToScreenColumn(0, 4));
+        assertEquals(5, doc.documentToScreenColumn(0, 5));
+        assertEquals(7, doc.documentToScreenColumn(0, 6));
+        assertEquals(13, doc.documentToScreenColumn(0, 12));
+        assertEquals(15, doc.documentToScreenColumn(0, 13));
+    },
+
+    "test: convert document to scrren coordinates with leading tabs": function() {
+        var doc = new ace.Document("\t\t123");
+        doc.setTabSize(4);
+
+        assertEquals(0, doc.documentToScreenColumn(0, 0));
+        assertEquals(4, doc.documentToScreenColumn(0, 1));
+        assertEquals(8, doc.documentToScreenColumn(0, 2));
+        assertEquals(9, doc.documentToScreenColumn(0, 3));
+    },
+
+    "test: convert screen to document coordinates" : function() {
+        var doc = new ace.Document("01234\t567890\t1234");
+        doc.setTabSize(4);
+
+        assertEquals(0, doc.screenToDocumentColumn(0, 0));
+        assertEquals(4, doc.screenToDocumentColumn(0, 4));
+        assertEquals(5, doc.screenToDocumentColumn(0, 5));
+        assertEquals(5, doc.screenToDocumentColumn(0, 6));
+        assertEquals(5, doc.screenToDocumentColumn(0, 7));
+        assertEquals(5, doc.screenToDocumentColumn(0, 8));
+        assertEquals(6, doc.screenToDocumentColumn(0, 9));
+        assertEquals(12, doc.screenToDocumentColumn(0, 15));
+        assertEquals(13, doc.screenToDocumentColumn(0, 19));
     }
 });
\ No newline at end of file
diff --git a/src/test/ace/NavigationTest.js b/src/test/ace/NavigationTest.js
index 37b84579..f7eee858 100644
--- a/src/test/ace/NavigationTest.js
+++ b/src/test/ace/NavigationTest.js
@@ -11,7 +11,7 @@ var NavigationTest = TestCase("NavigationTest",
         var editor = new ace.Editor(new MockRenderer(), doc);
 
         editor.navigateFileEnd();
-        var cursor = editor.getSelection().getCursor();
+        var cursor = editor.getCursorPosition();
 
         assertTrue(editor.getFirstVisibleRow() <= cursor.row);
         assertTrue(editor.getLastVisibleRow() >= cursor.row);
@@ -32,32 +32,32 @@ var NavigationTest = TestCase("NavigationTest",
 
         editor.navigateTo(0, 0);
         editor.gotoLine(101);
-        assertPosition(100, 0, editor.getSelection().getCursor());
+        assertPosition(100, 0, editor.getCursorPosition());
         assertEquals(90, editor.getFirstVisibleRow());
 
         editor.navigateTo(100, 0);
         editor.gotoLine(11);
-        assertPosition(10, 0, editor.getSelection().getCursor());
+        assertPosition(10, 0, editor.getCursorPosition());
         assertEquals(0, editor.getFirstVisibleRow());
 
         editor.navigateTo(100, 0);
         editor.gotoLine(6);
-        assertPosition(5, 0, editor.getSelection().getCursor());
+        assertPosition(5, 0, editor.getCursorPosition());
         assertEquals(0, editor.getFirstVisibleRow());
 
         editor.navigateTo(100, 0);
         editor.gotoLine(1);
-        assertPosition(0, 0, editor.getSelection().getCursor());
+        assertPosition(0, 0, editor.getCursorPosition());
         assertEquals(0, editor.getFirstVisibleRow());
 
         editor.navigateTo(0, 0);
         editor.gotoLine(191);
-        assertPosition(190, 0, editor.getSelection().getCursor());
+        assertPosition(190, 0, editor.getCursorPosition());
         assertEquals(180, editor.getFirstVisibleRow());
 
         editor.navigateTo(0, 0);
         editor.gotoLine(196);
-        assertPosition(195, 0, editor.getSelection().getCursor());
+        assertPosition(195, 0, editor.getCursorPosition());
         assertEquals(180, editor.getFirstVisibleRow());
     },
 
@@ -66,12 +66,41 @@ var NavigationTest = TestCase("NavigationTest",
 
         editor.navigateTo(0, 0);
         editor.gotoLine(12);
-        assertPosition(11, 0, editor.getSelection().getCursor());
+        assertPosition(11, 0, editor.getCursorPosition());
         assertEquals(0, editor.getFirstVisibleRow());
 
         editor.navigateTo(30, 0);
         editor.gotoLine(33);
-        assertPosition(32, 0, editor.getSelection().getCursor());
+        assertPosition(32, 0, editor.getCursorPosition());
         assertEquals(30, editor.getFirstVisibleRow());
+    },
+
+    "test: navigate from the end of a long line down to a short line and back should maintain the curser column": function() {
+        var editor = new ace.Editor(new MockRenderer(), new ace.Document(["123456", "1"]));
+
+        editor.navigateTo(0, 6);
+        assertPosition(0, 6, editor.getCursorPosition());
+
+        editor.navigateDown();
+        assertPosition(1, 1, editor.getCursorPosition());
+
+        editor.navigateUp();
+        assertPosition(0, 6, editor.getCursorPosition());
+    },
+
+    "test: reset desired column on navigate left or right": function() {
+        var editor = new ace.Editor(new MockRenderer(), new ace.Document(["123456", "12"]));
+
+        editor.navigateTo(0, 6);
+        assertPosition(0, 6, editor.getCursorPosition());
+
+        editor.navigateDown();
+        assertPosition(1, 2, editor.getCursorPosition());
+
+        editor.navigateLeft();
+        assertPosition(1, 1, editor.getCursorPosition());
+
+        editor.navigateUp();
+        assertPosition(0, 1, editor.getCursorPosition());
     }
 });
\ No newline at end of file
diff --git a/src/test/ace/VirtualRendererTest.js b/src/test/ace/VirtualRendererTest.js
index 506fdabc..3a943485 100644
--- a/src/test/ace/VirtualRendererTest.js
+++ b/src/test/ace/VirtualRendererTest.js
@@ -1,62 +1,5 @@
 var VirtualRendererTest = new TestCase("VirtualRendererTest", {
 
-    "test: convert document to screen coordinates" : function() {
-        var el = document.createElement("div");
-        var renderer = new ace.VirtualRenderer(el);
-
-        var doc = new ace.Document("01234\t567890\t1234");
-        doc.setTabSize(4);
-        renderer.setDocument(doc);
-
-        assertEquals(0, renderer.$documentToScreenColumn(0, 0));
-        assertEquals(4, renderer.$documentToScreenColumn(0, 4));
-        assertEquals(5, renderer.$documentToScreenColumn(0, 5));
-        assertEquals(9, renderer.$documentToScreenColumn(0, 6));
-        assertEquals(15, renderer.$documentToScreenColumn(0, 12));
-        assertEquals(19, renderer.$documentToScreenColumn(0, 13));
-
-        doc.setTabSize(2);
-
-        assertEquals(0, renderer.$documentToScreenColumn(0, 0));
-        assertEquals(4, renderer.$documentToScreenColumn(0, 4));
-        assertEquals(5, renderer.$documentToScreenColumn(0, 5));
-        assertEquals(7, renderer.$documentToScreenColumn(0, 6));
-        assertEquals(13, renderer.$documentToScreenColumn(0, 12));
-        assertEquals(15, renderer.$documentToScreenColumn(0, 13));
-    },
-
-    "test: convert document to scrren coordinates with leading tabs": function() {
-        var el = document.createElement("div");
-        var renderer = new ace.VirtualRenderer(el);
-
-        var doc = new ace.Document("\t\t123");
-        doc.setTabSize(4);
-        renderer.setDocument(doc);
-        assertEquals(0, renderer.$documentToScreenColumn(0, 0));
-        assertEquals(4, renderer.$documentToScreenColumn(0, 1));
-        assertEquals(8, renderer.$documentToScreenColumn(0, 2));
-        assertEquals(9, renderer.$documentToScreenColumn(0, 3));
-    },
-
-    "test: convert screen to document coordinates" : function() {
-        var el = document.createElement("div");
-        var renderer = new ace.VirtualRenderer(el);
-
-        var doc = new ace.Document("01234\t567890\t1234");
-        doc.setTabSize(4);
-        renderer.setDocument(doc);
-
-        assertEquals(0, renderer.$screenToDocumentColumn(0, 0));
-        assertEquals(4, renderer.$screenToDocumentColumn(0, 4));
-        assertEquals(5, renderer.$screenToDocumentColumn(0, 5));
-        assertEquals(5, renderer.$screenToDocumentColumn(0, 6));
-        assertEquals(5, renderer.$screenToDocumentColumn(0, 7));
-        assertEquals(5, renderer.$screenToDocumentColumn(0, 8));
-        assertEquals(6, renderer.$screenToDocumentColumn(0, 9));
-        assertEquals(12, renderer.$screenToDocumentColumn(0, 15));
-        assertEquals(13, renderer.$screenToDocumentColumn(0, 19));
-    },
-
     "test: screen2text the column should be rounded to the next character edge" : function() {
         var el = document.createElement("div");
         el.style.left = "0px";